Welcome to the forums!
When it comes to G12 I have only ever bought the pre-mix stuff (which is suprisingly expensive compared to the green stuff). As for how much the system itself takes, I'm not even sure how much my Mk3 takes, although after pulling one of the sensor and letting it drain from that point it then took about 4L to fill it back up.
I have read about people replacing coolant pumps and onyl needing 2 - 3L to re-fill the system, but I think they are quicker than me.
In my case I would get 2 x 4L and hope for the best... or ask the experts first. This sounds like one of those time we should wait for the Mk4 experts.
Bookmarks